The present invention is directed in general toward remote control apparatus and, more particularly, toward method and apparatus for programming the selected ones of a plurality of CATV channels which a user is authorized to receive.
Cable television (CATV) has become very popular in recent years. This is primarily due to the improved quality of audio/visual reception provided by CATV transmitters along with the increased channel selection which is provided.
Conventional means for providing CATV service to a user relies upon a channel authorization unit located within the user's residence (usually in close proximity to the user's television set) to insure that the user receives only channels he is authorized to receive. The channel authorization unit receives a plurality of CATV system channels supplied by the CATV transmitter via a dedicated communication link. The channel authorization unit is provided for supplying a plurality of selected channels to the user, which selected channels are those CATV system channels that the particular use is authorized to receive. Typically, the signals provided to the channel authorization unit are provided in a scrambled fashion to prevent the user from bypassing the channel authorization unit and pirating unauthorized channels. Therefore, the channel authorization unit is also adapted to perform a descramble function such that the signal provided to the user's television set is in proper form.
In order to screen channels such that the user only receives those selected channels which he has been authorized to receive, the channel authorization unit is typically preprogrammed by a system programmer before being installed in the user's residence. This preprogramming is usually done by programming a programmable read only memory (PROM), or other similar device, which device is then physically installed within the user's channel authorization unit. However, this method requires time for the system programmer to disassemble the authorization unit and install the PROM device with the newly authorized channels. Further, because these systems require replaceable programmable read only memories, a black market has developed wherein a user can obtain programmed memories from sources other than his CATV supplier. The user then installs the black market programmable read only memory in his unit such that he can receive channels for which he is not authorized.
It is, therefore, desirable to provide method and apparatus for programming a channel authorization unit which method and apparatus does not require physical disassembly of the unit. Additionally, it is desirable to provide a channel authorization unit which is not susceptible to piracy of unauthorized CATV channels.